Air lift pump



Oct. 18, 1955 E. WARREN ETAL 2,720,836

AIR LIFT PUMP Filed April 16, 1954 INVENTORJ 1455 E. Wages/v /Vqe/s waeesujc/mnsr MAMLQM United States Patent Ofiice 2,720,836 Patented Oct". 18, 1955 AIR LIFT PUMP Asa E. Warren and Marie WarrenSchavet, Menasha, Wis. Application April 16, 1954, Serial No. 423,662 8 Claims. (Cl. 103-5) This invention relates to an air lift pump.

According to the invention, the kinetic energy of the air does not act directly upon the water but rotates a propeller through which the air is discharged with an upward component from the individual blades, the orifices in the blades being small enough to require the air to issue in the form of small bubbles which, distributed in the rising column of water, reduce the weight of the column and facilitate thepumping action.

In the preferred embodiment disclosed, the air is used in three difierent ways to lift water. In the first place, the reaction of the air issuing from the propeller blades rotates the propeller to cause the blades to exert a lifting action. It is important that the blades operate on solid water prior to the admixture of the air bubbles therewith. In the second place, the residual kinetic energy of the air as it escapes from the propeller blades is released with an upward component whereby lifting action is exerted on the water which has already been accelerated by the blades. In the third place, the air which has already been used twice is finely divided into small bubbles and distributed throughout the rising column of water to reduce the weight thereof and thus to facilitate the action of the impeller. In actual tests, a device constructed in accordance with the present disclosure has produced a flow of forty-eight gallons a minute as compared with twentyseven gallons per minute produced by a conventional air jet pump using the same air source in the same well.

In addition to the generic aspects of the invention as above outlined, the preferred embodiment features a coaxial organization in which the air pipe is centered within the water pipe and communicates with a hollow spindle upon which the impeller is journaled for rotation. A cap for the lower end of the spindle carries a spider which positions the spindle centrally within the water pipe and serves as a thrust bearing for the impeller. An additional spider may be used above the impeller if desired.

Another detail of the invention has to do with the specific impeller which comprises a tubular hub having radial vanes of triangular form in end elevation, the upper surfaces of each such vane being slightly concave and the rear surfaces of each such vane being rearwardly inclined to provide a bevelled surface through which the vent apertures open in a rearward and upward direction.

In the drawings:

Fig. l is a view in axial section showing my pump installed in a Well casing.

Fig. 2 is an enlarged detail view in axial section through the pump.

Fig. 3 is a view taken in section on line 33 of Fig. 2.

Fig. 4 is a view taken in section on line 44 of Fig. 2.

Fig. 5 is a detail view of the impeller in perspective.

Fig. 6 is a detail view taken in section on the line 66 of Fig. 2.

The pump may be used in any well such as that represented by the casing 7. The pump comprises a water lift pipe 8 lowered into the well and having centrally disposed therein an air supply pipe 9. At its lower end 2 the supply pipe 9 is connected by coupling 10 with a tubular spindle 11 desirably shouldered at 12 to receive the positioning spider 13. However, this spider is nonessential, since the spindle is otherwise positioned and the thrust of the impeller rotor is downward.

The portion 14 of the spindle comprises a cylindrical bearing surface upon which rotates the hub 15 of the impeller which is separately illustrated in Fig. 5. This hub has an interior peripheral channel at 16 communicating with the interior of the tubular spindle 11 through a member of ports 17. Externally the hub 15 carries the vanes 20 which, in the instant exemplification, are four in number. These vanes are triangular in end elevation, as clearly appears in Figs. 5 and 6. The leading edge 21 of each is sharp. The upper surface 22 may, if desired, be concave, although this is unimportant. A hole 23 opening radially from channel 16, as shown in Figs. 2 and 4, is closed by a plug 24 at the outer end of each blade. The rearwardly bevelled or inclined surface 25 of each blade is bored with one or more small openings 26 which lead upwardly and rearwardly from the respective bores 23, as best shown in Fig. 5 and Fig. 6.

The lower end of the tubular spindle 11 is closed by a cap 28 which may be fixed to the spindle by a taper pin 29. The cap carries positioning spider 30 for centering the spindle within the water pipe 8. Large openings are provided in the spiders 30 and 13 to facilitate upward flow of water from the body of water in the well in response to the pumping action of ,the device.

When air under pressure is supplied through pipe 9, the air escapes through port 17, channel 16 and radial bores 23 and discharge ducts 26. Desirably a number of such ducts are provided in each blade.

The reaction of the escaping air drives the impeller at a fairly high speed of rotation, causing the upper surfaces 22 of the respective blades to impel the water upwardly within pipe 8. The sharp leading edges 21 of the blades are always acting in solid water into which air bubbles have not yet been discharged.

The form of the blades and the small size of the discharge orifices 26' assure that the air will be subdivided into small bubbles as released in the column of water which is already in motion upwardly in the pipe. The effect of the air is not only to reduce the weight of the column of Water but to expand the mass of the water comprising the column, thereby further accelerating flow in an upward direction. Reduction in weight of the column facilitates the action of the propelling blades by reducing back pressure.

As already noted above, the direction of the orifices 26 has a distinct upward component so that any residual kinetic energy in the air is likewise exerted directly on the water to produce upward flow.

As a result of the conjoint action of these several factors, the flow of water produced by my pump is nearly doubled as compared with competitive air lift pumps.

We claim:

1. A reaction jet impeller air lift water pump comprising the combination with a water discharge pipe and an air supply pipe substantially co-axially disposed therein, of a tubular spindle with which the air supply pipe communicates, said spindle having an external bearing surface and ports opening therethrough, an impeller including a hub rotatably mounted on the bearing surface and provided with blades having water propelling surfaces inclined with reference to a plane normal to the axis of impeller rotation, said blades further having relatively less inclined lower surfaces, the forward edges of said blades being the apex of the angles between their respective said surfaces and third surfaces constituting.

the trailing edges and joining said water propelling surhub.

7 air pp y P p faces and said lower surfaces, said blades being further provided with outwardly opening passages communi-,

eating with said ports,.said blades having ducts opening rearwardly from said passages to orifices in said third surfaces for the jetting of 'air received through said pipe and spindle, whereby the reaction of the escape of such air propels the impeller to advance a water upwardly through said pipe,.the bubbles of escaping air increasing the volume of. such .water and reducing the weight thereof to reduce the load on the impeller and expedite flow.

V 2. The device of claim 1 in which said third surfaces are inclined upwardly and forwardly from the rear of said lower surfaces whereby the air issuing from said orifices is finely divided by turbulence behind said blades.

3. The device of claim 1 in which the orifices of the several blades have an upward component of direction, whereby residual kinetic energy of released air is exerted in a water lifting direction.

4. The device of claim 1 in which said spindle has a terminal closure including a spindle centering spider means bearing internally upon said water discharge pipe which further provides a thrust bearing for the impeller 5. Apumping device to be inserted in a water discharge pipe and operated by compressed air from an said device comprising the combination with artubular spindle having a bearing portion of reduced diameter and provided with ports opening through said bearing portion, of a closure. for the end of the spindle encircling the bearing section having relatively sharp leading edges and relatively blunt rear surfaces, said blades having outwardly leading from said channel and hav-.

opening passages ing orifices rearwardly and upwardly opening from said passages through the rear blade surfaces for the reaction propulsion of the impeller and the upward jetting of water set in motion by the blades and the release of air in the form of bubbles distributed by said blades throughout the moving column of water to reduce the weight thereof and thereby to reduce the back pressure portion and providing a thrust bearing surface, said closure further comprising on the impeller. and, by increasing the volume of the V 7 water, to accelerate .its upward movement inv the water' discharge pipe. V

6. The device of claim 5 .in which said closure and said spindle are provided with aligned openings, and a tapered pin engaged in said openings to secure said closure to said spindle.

7. The device of claim 6 in which there is a second means for centering said spindle in said water discharge pipe which is secured to said spindle at the upper end of said bearing portions of reduced diameter and which provides a second thrust bearing means, the hub of the impeller being axially positioned between said two thrust bearing means and having bearing engagement with both said means.

8. A pumping device to be inserted in a water discharge pipe and operated by fluid from a fluid supply pipe, said device comprising the combination with a tubular spindle having a shoulder and a bearing portion of reduced and provided with ports diameter beyond. the shoulder opening through said bearing portion, of a closure for the end of the spindle encircling the bearing portion and providing a first thrust bearing surface, said closure further comprising a first means for centering the spindle within the water discharge pipe, an impeller comprising a hub rotatably mounted on the bearing surface of the spindle and provided in its inner periphery with passage means communicating with said ports, blades mounted on the hub opening'from said passage means, a second means for centering the spindle within the water discharge pipe encircling said bearing portion and providing a, second thrust bearing surface opposed to said first thrust hearing surface, axially remote generally radial and through which said passage means extend, and having fluid delivery ducts the side of said second centering means.

from said second thrust bearing means being in abutting relationship with said shoulder on said spindle, said hub being axially confined between said. 

